The full definition
IOP and PHP are the two structured outpatient levels of care in the behavioral health continuum (below residential, above standard outpatient). IOP runs 9–15 hours/week (CPT H0015), typically 3 days × 3 hours of group + individual therapy. PHP runs 20–30 hours/week (CPT H0035), typically 5 days × 5 hours and is sometimes called 'day treatment' or 'hospital diversion.' PHP is a higher acuity level requiring more documentation and payer authorization scrutiny.
Why it matters in practice
Most behavioral health and addiction treatment centers offer both IOP and PHP, with patients stepping down from PHP to IOP as they stabilize. Practices need software that supports both code sets, both documentation rhythms, and the distinct authorization workflows each payer category requires.
Real-world examples
- An addiction treatment center running 4 PHP cohorts (Mon-Fri, 9am-3pm) plus 6 IOP cohorts (3 days/week, evening and morning)
- A behavioral health practice stepping a patient from PHP down to IOP after 4 weeks
- An eating disorder treatment center running both IOP and PHP with different clinical curricula
Inside Velant
Velant supports the full IOP/PHP code set (H0015, H0035, H0001, H0005) with payer-specific authorization tracking, group session documentation, and continuing care review workflows.
Related terms
- EPCS (Electronic Prescribing of Controlled Substances)A DEA-regulated electronic prescribing standard for Schedule II–V controlled substances, requiring identity proofing, two-factor authentication, and audit logging of every prescription event.
- 270/271 Real-Time Eligibility VerificationThe HIPAA standard transaction pair used to verify a patient's insurance coverage in real time. 270 is the request to the payer; 271 is the response.
- 837P Electronic Claim SubmissionThe HIPAA-standard electronic claim format for professional services (physician, behavioral health, outpatient) — the most common claim type for non-hospital providers.